Nice B.
Just curious to know how big the "ears" are on the fuel cap? This is something i'm looking at more and more of late with the ally caps for dating purposes. I'm trying to determine whether big ears are early and smaller ears are later, or the other way around!! (unless of course its a complete hotchpotch of mixed up parts from all years)
What does your gut instinct tell you with flywheels!
Preservation (rather than full on bling and shiny) is more the way i like to go these days with my seagulls. Keeps 'em looking honest.
H-A might be the better person to ask with how to preserve the tank.
With the jumping into gear, i've found that the adjustment on the clutch rod is quite critical on some 102's. They seem to like it on the tight side

rather than loose. It helps too if the exhaust clamp has the little "FLAT" section for the rod to rest against. Without this "flat" the rod tends to slip off it's perch and drop down leading to an instant jump into gear! Annoying, but it does happen. Tension on the clutch lever can also be of benefit here. Too loose and it might not hold in neutral, too tight and the lever might not have the full range of movement required to engage and disengage the clutch.
Trial and error with some of it.
Jon